In this study, strength of epoxy adhesively bonded scarf joints of dissimilar metals, namely SUS304 stainless steel and YH75 aluminium alloy was examined on several scarf angles and various bond thickness under pure mode I loading. Scarf angle, θ=45°, 60° and 75° were employed. The bond thickness, t between dissimilar metals was controlled to be ranged between 0.1 mm to 1.2 mm. Finite element analysis was also executed to investigate the stress distribution in the scarf joints by ANSYS 11 code. Stress multiaxiality of scarf joints slightly increases as the scarf angle increases. From analytical solutions, stress singularity exists most pronoundcedly at steel/adhesive interface corner of joint having 45° to 75° scarf angle and this is in agreement with FE analyses and in confirmed by fracture observations wherein the fracture has always been initiated at this point. The apparent Young's modulus of adhesive layer in scarf joints is found to be 1.5〜5 times higher than those of bulk epoxy adhesive, which obtained from tensile tests.

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Recently, laminated materials are used in many fields such as vehicles. Material combination is effective to control fracture. Laminated materials are expected to protect fracture. When a crack appear in it and develop, it may be able to stop crack developing at interface. In this study, we did impact three-point bending test and determined dynamic stress intensity factor useing cuastics method and high speed camera. Result shows that material combinations are enable to control fracture.

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The 6061 aluminum alloy is being used as a liner material of a high-pressure hydrogen tank for fuel cell vehicles. At present in Japan, maximum pressure is limited to 35MPa which causes the mileage per a filling to be less than that of gasoline vehicles. Thus, raising the initial pressure to 70MPa by replacing the 6061 alloy by a higher-strength aluminum alloy is demanded to increase the mileage. However, it is known that some aluminum alloys cause hydrogen embrittlement. In addition, the cause of hydrogen embrittlement and behavior of hydrogen in materials has not been elucidated yet. In order to check the safety of the hydrogen tank, investigation on the hydrogen assisted embrittlement as well as on the behavior of hydrogen is required. Slow strain rate technique (SSRT) test and thermal desorption spectroscopy (TDS) can be used to examine the resistance to hydrogen embrittlement and analyze the hydrogen behavior, respectively. In this study, the resistance to hydrogen embrittlement of a 6061 aluminum alloy with high Si content that has higher strength than ordinary 6061 alloy has been studied by SSRT tensile test. Also, the behavior of hydrogen has been investigated by means of TDS.

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Fuel cell vehicles (FCVs) are being developed as a measure of resolving global environment problems. In the FCVs, high-pressure (35MPa) hydrogen has been being used as the fuel, contained in type-3 tank composed of 6061-aluminum-alloy liner and surrounding carbon-fiber-reinforced-plastics layer. However, the mileage per a filling of FCVs is not as long as that of gasoline vehicles. Thus, replacing the 6061 alloy by a high-strength aluminum alloy is demanded to increase the mileage by raising the initial pressure to 70MPa. In order to check the safety of the hydrogen tank, investigation on the behavior of hydrogen as well as on the hydrogen assisted embrittlement is required. Although hydrogen microprint technique (HMPT) has been known to be effective to investigate the hydrogen behavior, only a few percents of hydrogen was reported to be detectable. Ion-plating has been report to increase the detection efficiency of hydrogen. In this research, hydrogen behavior in ion-plated pure aluminum plate during tensile deformation has been investigated by means of HMPT. Aluminum plate of 99.99% purity was ion-plated with Sn and then charged with hydrogen either with or without tensile deformation. In either specimen no hydrogen was detected. The results obtained were discussed in comparison with the previous report in terms of plating conditions.

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White layers generated on rail surface due to wheel spin or skids are thought to be an important factor of rail cracks, shellings and subsequent breakage after passing tonnage accumulates. It is of great beneficial to rail maintenance to clarify a correlation between them. We have reported that it is able to detect white layers by using Superconducting Quantum Interference Devices (SQUID). In order to run Nondestructive Tests (NDT) in the field, we have developed a noise feedback system to stably operate a SQUID under environmental noise. In this study, we confirmed that the NDT scanner is able to detect white layers.

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We measured the magnetic flux desities and the magnetization curves on neutron irradiated fast reactor grade type 316 stainless steels by a flux gate sensor and a newly developed vibrating sample magnetometer, respectively. As the result, it was revealed that there is a good relationship between magnetic property and dose, one of representative irradiation damage parameters. This result shows the possibility of nondestructive evaluation of neutron irradiation damage based on magnetic properties.

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The 6061 aluminum alloy is being used as a liner material of a high-pressure hydrogen tank for the fuel cell vehicles. Since higher maximum filling pressure is demanded to achieve longer mileage per fuel filling, application of other alloys having higher strength is considered. However, some aluminum alloys are reported to cause hydrogen embrittlement. The cause of hydrogen embrittlement and behavior of hydrogen in the alloy has not been clarified yet. Hydrogen microprint technique (HMPT) is an effective method to investigate the hydrogen behavior, in which the reaction between silver bromide emulsion and atomic hydrogen emitted from the sample is used. In the present study, the behavior of hydrogen in 6061 aluminum alloy and aluminum with 99.99% purity has been investigated by means of HMPT. Two kinds of hydrogen have been in concern: (i) environmental (external ) hydrogen introduced by cathodic electrolytic charging and emitted naturally, (ii) impurity (internal ) hydrogen emitted by plastic deformation.

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The Aluminum alloy/rubber joints are applied to automotive suspension to maintain high level of silence and comfortableness. However, aluminum alloy is directly joined with rubber. Therefore it is necessary to suppress both corrosion of aluminum alloy and decohesion of rubber. In this study, the durability of aluminum alloy/rubber joints under corrosive atmospheres has been examined on several aluminum alloys: extruded 6N01, gravity-die-cast AC4CH, pressure-die-cast ADC12, ADC3 and Silafont36 alloys. Among them, only pressure-die-cast ADC12 alloy/rubber joint caused decohesion. It was found from the observations on the cross-sectional microstructure that the corrosion of ADC12 alloy was the major cause for the decohesion. This corrosion was attributable primarily to the high contents of harmful elements for corrosion such as Cu and Fe, and secondary to the fine microstructure caused by the pressure-die-casting process.

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Eddy Current Testing (ECT) already plays very important role in quite wide field such as airline and power plants for maintenance, ironworks for production. Although it is excellent inspection method, physical principle of ECT blur the flaw image. Author have proposed a method to reconstruct more finer flaw image from ECT signal with signal processing. The method is based on the simple relationship between signal and source are described by a convolution of response function and flaw shape. The method was applied to ECT data of artificial machined flaws on SUS316 plate. The obtained results shows remarkable fact that insure the validity of the method to variety types of flaw shape.

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This paper presents a newly developed magnetic probe for nondestructive evaluation of pipe wall thinning. The proposed magnetic probe can measure the magnetic flux density, B, and the magnetic field strength, H, for high accuracy of the evaluation of wall thinning. Some conditions of pipe wall thinning were evaluated by this probe, and the numerical analysis by FEM was carried out to improve the performance of the proposed magnetic probe.

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Carburization evaluation of 9Cr-1Mo steel furnace tube of the CCR (Continuous Catalyst Regeneration Reformer) is an important technology which is required for the safe and stable operation of petrochemical plants in long term. Application of the nondestructive evaluation to determine the inside and outside carbon density distribution were examined by combining both the magnetic measurement method (Non-Linear Harmonics (NLH) method) for total carbon density of thickness and portable optical emission spectroscopic analysis equipment for outer surface carbon density. As the result, it is thought that an individual estimation of the inside and outside carburization is possible by this nondestructive evaluation method.

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There are some fatigue damage estimation methods of the austenitic stainless steel (SUS304 and S316) that uses the change of electromagnetic properties by fatigue. For instance, they are the remanent magnetization method, the excitation method, and so on. It is well known that the relation between fatigue damage and the remanent magnetization of them is simple, clear, and reproducible. On the other hand, the excitation method such as the inductance method using a pancake type coil can use easily on the site. In this paper, two fatigue evaluation methods such as the remanent magnetization method and the excitation method are introduced. In addition, we report on the result of comparing the fatigue evaluation performances of two methods.

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Recently, as the demands for guarantee in safety and reliability of structures are increased, non-destructive testing is of great importance. Especially, Eddy Current Testing (ECT: An electromagnetic non-destructive testing) has better prospects than the others due to its simple equipment and non-contact testing technique. In this study, fatigue tests of the ferromagnetic mild steel SS400 were conducted and then, by means of ECT sensor, we evaluated this material's fatigue damage, crack initiation and also its propagation.

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EMAT was proposed for testing large structural meterials. The signal's property was analized and its signal noise was shown to be removed sucessfuly by statistical methods. The methods to reconstruct 3-D image of inside area of samples usinng a time series of signal data observed by EMAT was shown.

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A yoke probe, which has a winding coil for excitation, a pickup coil to detect magnetic flux and a U-shaped magnetic single-yoke, has developed and examined to evaluate the magnetic property like coercive force using the probe without machining of specimens. Ac permeability was also evaluated indirectly by means of impedance measurement with the proposed probe. Then measured magnetic parameters were correlated with mechanical parameter like Vickers hardness. Additionally the impedance distribution of the deformed steels was evaluated. Impedance distribution will reflect the distribution of mechanical properties of the deformed steels. Our trail for NDE of degradation of materials using magnetic single-yoke probe is introduced and its potential is discussed.

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Non-destructive evaluation of defect shape for ferromagnetic structural material SS400 was performed by magnetic flux leakage technique using a fluxgate sensor. Changes in leakage magnetic flux density were measured by varying the defect depth. With increasing the defect depth the leakage magnetic flux density also increased and it was found that the defect depth could be estimated by measuring the relationship between the leakage magnetic flux density and the defect depth previously. In order to estimate defects which have more complicated shapes, inverse analyses were also performed. The relationship between the magnetic flux density and magnetic moment of the defect was formulated. By using the singular value decomposition technique distribution of the magnetic moment of the defect was calculated from the simulated magnetic flux density which contained 5% noises at most and it was found that the defect shape and size were successfully obtained.

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The notch size effect in the off-axis compressive strength of a unidirectional CFRP at high temperature (100℃) has been studied. This study also aims to develop engineering methods for predicting the off-axis notched strengths. Static compression tests were carried out on center hole (CH) specimens with different hole diameters and different fiber orientations. Experimental results showed that the off-axis compressive strengths of the CH specimens become smaller with increasing hole diameter, except for the 0° and 10° specimens. The off-axis compressive notch sensitivity is compared with the off-axis tensile notch sensitivity observed in the previous study, although the size of the specimens used in those tests are different. This comparison demonstrates that the compressive notch sensitivity is lower than the tensile one. The off-axis compressive notched strengths were predicted using the off-axis notch sensitivity model. This model can efficiently predict the off-axis notch sensitivity, but they fail to predict the off-axis notched strengths distributed in the vicinity of the notch insensitive line.

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The effects of notch size and fiber orientation on the off-axis fatigue strength of the notched fiber metal laminate GLARE-3 are examined. Off-axis fatigue tests are performed on notched (center open hole) specimens with different fiber orientations. It is clearly observed that the fatigue strength of notched GLARE-3 exhibits not only notch size dependence but also fiber orientation dependence. A new criterion for the fatighe failure of notched orthotropic materials is developed which allows prediction of their fatigue lives for any notch size and for any multiaxial state of stress. The proposed fatigue failure criterion is an extension of the fatigue damage mechanics model which was earlier developed for unnotched orthotropic materials. A major advantage of the proposed method is to allow efficient prediction of the S-N curves of the notched GLARE-3 laminates using only a limited amount of test data: the notched strengths and the S-N curves for unnotched specimens. It is demonstrated that the off-axis S-N relationship for notched GLARE-3 can accurately be predicted by means of the proposed fatigue failure criterion, regardless of the notch size and fiber orientation.

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The effect of stress ratio on constant amplitude fatigue behavior of a unidirectional CFRP laminate has been examined. Applicability of a rational fatigue life prediction method based on constant fatigue life diagram has also been discussed. First, constant-amplitude fatigue tests were performed at room temperature on coupon specimens with different fiber orientations at different values of stress ratio. The experimental results show that the fatigue strength of the unidirectional composite becomes lower for fatigue loading with a larger value of alternating component, regardless of fiber orientation. The stress amplitude becomes largest for the fatigue loading at the critical stress ratio that is equal to the ratio of compressive strength to tensile one. Second, the anisomorphic constant fatigue life diagram was tested which allows efficient construction of constant fatigue life diagram on the basis of the static strengths in tension and compression and the reference S-N relationship for the critical stress ratio. The method was found to be applicable to the fatigue in the fiber direction, while it failed for the other off-axis fiber orientations.

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Effects of variable fatigue loading with alternate R-ratios on the fatigue life of a quasi-isotropic woven fabric CFRP laminate have been studied. First, constant amplitude fatigue tests are performed on plain coupon specimens of the CFRP laminate at different stress ratios in order to obtain a baseline set of fatigue data for this investigation. Then, variable R-ratio fatigue tests are carried out during which the stress ratio of fatigue loading alternates between two values keeping the level of maximum fatigue stress constant. The fatigue life of the composite under variable R-ratio loading is examined not only for different pairs of stress ratios, but also for different levels of maximum fatigue stress. By comparing the fatigue lives under constant and variable R-ratio fatigue loading conditions, the effect of alternation in R-ratio on the fatigue life of the CFRP laminate is elucidated. Experimental results demonstrate that a small change in R-ratio has a degrading effect and affects to reduce the total number of cycles to failure, while a large change in R-ratio brings about a retardation effect in damage accumulation, when the maximum fatigue stress is relatively high. the retardation effect due to variation in R-ratio disappears under fatigue loading with a low maximum fatigue stress. Finally, the anisomorphic constant fatigue diagram is applied to prediction of the fatigue life of the CFRP laminate subjected to the alternate R-ratio loading using representative cumulative fatigue damage rules.

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The effect of water uptake on the constant amplitude fatigue behavior of a quasi-isotropic plain-woven CFRP laminate at different stress ratios has been examined. First, constant amplitude fatigue tests are performed at room temperature on the specimens immersed in hot water until saturation and on the specimens that are not exposed to water environment. The fatigue strength due to water uptake was about eleven percent which was independent of stress ratio. Then, the full shapes of the constant fatigue life (CFL) diagrams for the laminates in dry and wet environments were identified using the fatigue test data obtained at different stress ratios, which are characterized by asymmetry, nonlinearity and gradual change in shape. Finally, the anisomorphic CFL diagram approach for composites, which was developed in an earlier study, was tested on the dry and wet CFRP laminates. It is demonstrated that the anisomorphic CFL diagram approach succeeds in adequately predicting the CFL diagrams for the quasi-isotropic laminate in wet as dry environment.

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Off-axis creep strengths of notched plain woven fabric CFRP laminates under constant load conditions at 100℃ were examined, and phenomenological modeling of creep rupture strength of notched specimens were attempted. First, static tension tests were performed on notched specimens with four different fiber orientations to examine the notch size dependence as well as the fiber orientation dependence of off-axis tensile strength. Then, off-axis creep rupture tests on notched specimens were performed for the four fiber orientations under constant tensile loading conditions at more than three stress levels. Test results showed that transient creep behavior was dominant until final rupture, regardless of fiber orientation and of notch size. The log-log plots of creep stress against the time to rupture were almost linear over the tested range of time. On the basis of these creep rupture data, a phenomenological creep rupture model was developed. It was elucidated that the creep damage mechanics model succeeded in adequately predicting the observed off-axis creep rupture time of the notched specimens.

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In this study, a time-dependent homogenization theory is rebuilt for periodic composite materials in which their unit cells are arranged with misalignment. As a numerical example, the transverse elastic-viscoplastic properties of unidirectional carbon fiber-reinforced plastics (unidirectional CFRPs) with misaligned cell arrangements are analyzed using the present theory. It is thus shown that the transverse elastic-viscoplastic anisotropy of the unidirectional CFRPs decreases with the increase of misalignment of the cell arrangement.

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A powder eutectic coating using Al and Ti powder on Fe substrate is performed by laser scanning method. It can be confirmed that one coating layer made by using Al, Ti and Fe metal powder sheet material shows high oxidation resistance. The concentration of aluminum in coating layer is successfully controlled by the controlling of the composition of the sheet material consist of Ti, Al and Fe elemental powder.

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High temperature gas cooled reactors (HTGRs) are designed to produce high temperature gas, and their research and development is carried out in the world wide. Nuclear graphites to be used for the reactors will be subjected to oxidation damage at high temperature over a long period of operation time. In this study, oxidation experiments were carried out under different shear stresses as well as under no applied stress. Moreover, tensile and compression tests were carried out to these oxidized specimens at room temperature. As a result, fine-grained isotropic graphites (IG-11 and IG-110) were weakened by the oxidation. The shear stress at the oxidation treatment gave the much decrease of the tensile strength of IG-110 after oxidation. Test results are discussed with shear stress effects in some detail.

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Since global warming and an energy problem are simultaneously solvable, researches on fuel cell's have been quite active now. Especially, a Solid Oxide Fuel Cell (SOFC) is expected as a new power generation system from having the highest power generation efficiency and exhaust heat emitted from high temperature operation can be used (cogeneration system). Zirconia-based ceramics have been used for an electrolyte substance of the fuel cell and moreover superplasticity has been found in many kinds of zirconia-based ceramics. A bonding of ceramics using superplastic superplastic ceramics powder as an interlayer has been reported that the joint has a bonding strength almost equal to that of the ceramics itself. In this study, sinter bonding of an electrolyte and electrodes was performed using an electric furnace and microwave heating equipment.

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In this paper, the use of the Ag NanoPaste^[○!R] as an insert material has been proposed to laser-weld AZ31B magnesium alloy with a thickness of 0.3 mm. Lap fillet welding of the sheet coated with the Ag NanoPaste^[○!R] was carried out by using a pulsed Nd: YAG laser in argon atmosphere. Characteristics of the weld and mechanical properties of the joint were examined. Weldability of the thin sheet AZ31B was successfully improved with the Ag NanoPaste^[○!R] under the optimized conditions of pulse energy 1.8 J, pulse duration 3.0 ms, repetition rate 80 Hz, and scan speeds between 450 to 600 mm/min. Other advantages are the increase of bond width, the reduction of weld defects, and the expansion of the range of process parameters, compared with insert-free welding. Weld joint efficiency improves up to 92% of the base metal, while that without the Ag NanoPaste^[○!R] was 84%.

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A new method to fabricate a micro-hole in metals is proposed in this work. Refractory metal powders such as Mo and very fine glass fibers of 100 μm in diameter were used for the fabrication. It utilizes thermal properties mismatch between the metal powder and the fiber. Sintering at a temperature between their melting points causes glass to evaporate leaving a targeted shape of hole and densify the metal powder. Green compacts were prepared at various compressive loads and then subjected to sintering at temperatures below the melting points of the metal powder. The inspected hole after sintering exhibited circular cross-section and straightness of the hole. The inspection of the sintered part confirmed that the method is promising to fabricate micro-holes in metals.

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It is known that plastic deformation of magnesium is affected by texture. In this study, texture and residual stress of magnesium after deformation is measured by neutron diffraction. After the deformation, residual stress is strongly remained in (001) grains of normal direction. As a result, this residual stress caused by anisotropic deformation behavior of (hkl) grains result in poor plastic deformation of magnesium.

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Recently, magnesium alloy have drawn much attention as an appropriate material for mobile appliances because the alloys are very light in weight. As well known, plastic working of magnesium alloys are quite difficult stemmed from their hexagonal close-packed lattice structre. We have successfully developed a new boss forming process on a thin plate of light alloys in the circumferential environment. In this study, microstructures and some mechanical properties of the bosses shaped from an AZ31Mg alloy plate are examined and discussed. We have found that the impact strength of the bosses is about the same as or larger than that of the base alloy.

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Friction stir welding (FSW) is a kind of solid state bonding method developed by The Wekling Institute (TWI), and is a novel welding method for light metals and alloys. It is now well known that FSW'ed zone has an equixial and fine-grained microstructure. Therefore, many researchers have been paid attention to this as a microstructure contol method for variety of alloys including Al and Mg alloys; it is now called Friction Stir Processing (FSP). Up to date, however, there have been only a few reports on the FSP that have been applied to refine the grain size of large areas in the alloys. In the present study, we have carried out multi-pass FSP experiments on a high strength 7075Al alloy. We have found that Pass Boundary Zone (PBZ) appeares in the region between successive passes. In the PBZ the existence of many sub-grains was found. The influence of the PBZ are discussed in some detail.

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The mechanisms of microstructural evolution and mechanical behavior have also been studied by many researchers. In the present study, severely drawn low-carbon ferritic steel wire is investigated to clarify the mechanisms of high tensile strength. Neutron diffraction showed the existence of hkl intergranular residual stress, which is considered to cause the discrepancy between the hardness and tensile strength. The reasons of higher tensile strength achieved by drawing in comparison with other severe deformation processes, like ARB is estimated to be texture, residual intergranular stress and high dislocation density.

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It is significant to develop quantitative measurement to investigate microstructural factors for evaluating strength and fracture mechanism of material. Microstructural factors for bulky specimen can be measured by neutron diffraction. In this study, measuring method of texture by angler dispersive neutron diffraction was evaluated by profile analyses.

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The interactions between the gradient magnetic field and motion and how those movements are reflected on MRI image are discussed. It is suggested that the motion sensitizing gradient (MSG) which is generally used in MRE sequence is not necessary and the main selecting mechanism of the vibrating frequency is the synchronization between the vibrational motion and repetition time (TR).

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The tissue engineering approach to repair damaged bone and articular cartilage has been clinically attempted. In this study mechanical properties of cartilage and regenerated cartilage were measured by a viscoelastic spectrometer and an Instron-type universal testing machine. Internal structure analysis was made by a microfocus X-ray computed tomography.

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The function of the articular cartilage depends on transfer of the water from the tissue. The course of changes of the Apparent Diffusion Coefficient (ADC) and Magnetization Transfer Contrast (MTC) effect (Ms/Mo) of articular cartilage during mechanical compression were observed for evaluation of the cartilage function as extra vivo and in vivo study. On the extra vivo study, the ADC and Ms/Mo of the bovine cartilage decreased under compression, and increased by removal of compression. These results suggest that water content in the cartilage decreased, internal pressure increased, and a gap of the extracellular matrix decreased due to transformation of the collagen meshwork. Furthermore, the Ms/Mo in patellar cartilage slightly changed between with and without weight bearing in healthy subjects. This result suggests that water content or hydrate states within patellar cartilage changed by weight bearing. This extra vivo study also provides sample experimental support for our recent in vivo study.

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In recent years, an elastography has come to be performed using ultrasound imaging (US) of magnetic resonamce imaging (MRI). Existing MR elastography (MRE) pulse sequence was build the several bipolar magnetic field gradients (motion sensitizing gradient: MSG) into a conventional MR pulse sequence, and was synchronizes the vibration to imaging object and MSG. However, built-in MSG extends echo time (TE) and extension of TE dose the debasement of signal to noise ratio (SNR), and the influence of magnetic susceptibility. The purpose of this study was we developed a high-speed MRE pulse sequence that does not need built-in MSG (no extension of TE), and was to examine the potential of this method by phantom experiment.

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MR Elastography is noninvasive MRI method that utilizes propagating acoustic waves to determine elastic properties of tissue. Mechanical actuator provides cyclic motion synchronized to the MRI sequence. In preceding study, pneumatic vibrator is often applicable because it's completely compatible to MR environment. But this vibration characteristic is variable and need to be measured. In this study, development of pneumatic vibrator and its measurement system are reported. And then, frequency characteristics and correlation between mechanical amplitude and phase image contrast are examined.

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This paper reviews a current progress of ultrasonic elastography and discusses the point of difference and common point between magnetic resonance elastography (MRE) under development and the ultrasonic elastography, with the aim of exploring a possibility of complementary coexistence between the MRE and the ultrasonic elastography. The ultrasonic elastography has already been put to practical use and its clinical effectiveness is gradually being verified. On the other hand, if the MRE technology put to practical use, the MRE might become used as a complementary approach of the ultrasonic elastography to the diagnosis and so on, as analogized from the complementary relationship between conventional diagnostic ultrasonic imaging and MRI.

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Started in the 1960's, Several Type of Walking Aid Vision Substitution Device for visually impaired have been developed. The acute problem of these vision tactile substitution systems is the low amount of information causing the low tactile sensory resolution. Therefore, the most of system adopts the surrounding distance-tactile signal conversion, and it yet not enough to transmit surrounding state to user. This study aims at transmitting the position of human being using face-catch technology and new tactile display, and bring user to act, not passive, but active and voluntary communication.

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For the severely disabled people who are paralyzed from the neck down, eye-control input device takes an important role as computer input support interface as other tongue, EEG and EMG based input method. The eye input device has an advance in more direct operation feel than EEG, EMG stepping cursor moving input method. On the other hand, eye input device is still costly with conventional input device. This study aims at constructing moderating price to achieve mouse-control with goggle mounted cameras. This study consists of iris tracking performance part and mouse control algorithm part. Here, we adopted the adequate filtering and ellipse fitting for iris tracking. To cancel the head motion, this paper proposes the relative displacement based mouse control methods.

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Generally, a stroller is a vehicle that moves the flat ground. It is dangerous to go up and go down the stairs with an infant on a stroller. When going up the stairs, a parent (or baby sitter) should shoulder the folded stroller at the same time as holding the infant in his/her arms. Therefore, it becomes parents with a considerable load. On the other hand, a variety of stair climbing mechanisms are researched and developed. But these mechanism needs the large-scale system, for example an electrical motor or a fixed rail. In this study, we develop the stroller that is possible to go up/down the stairs smoothly without electricity. The suggested stroller is handled easier than an existing stroller.

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Product developments have been required improvements to performance, reliability, and shortened development times. We have developed "e-Design Handbook" for product developments. "e-Design Handbook" is a web-based engineering system which consists of calculation tools using analytical software. However, the response of the Web access slows as for the system when the calculation of lots of nodes is executed. We have cleared the problem by the development of "Remote Calculation Function" which cooperates automatically with a calculation server. This function is composed of the job management server and the job service manager. These two programs are executed the calculation jointly according to the network communication. The numerical result of the system is automatically distributed by email.

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Transport machine is developed by new material. Above all, it is important that transport design with safety, environmental compatibility and productivity in mind. Serious accident occurs frequently by transport capacity reinforced. So, in this research, it paid notice to automobile hub that occurs frequently since 1990's. Experiment analysis is used the stress freezing method in static load. And theoretical analysis is used finite element method. From both parties, it is calculated stress distribution in automobile hub model and stress concentration factor. In the result, it aims to optimization of design element, improvement of enhanced safety and base redefining research of automobile hub.

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The propagation behavior of a crack in SiO_2 is analyzed by using an atomistic simulation model. The relationship between crack velocity v and stress intensity factor K, v-K curve, is calculated based on the energy surfaces obtained by using this atomistic model. It is found that the calculated results coincide well with the experimental results in all three regions (region I, II, and III) of the v-K curve.

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In order to design high temperature components accurate constitutive equations of creep have been required. However specified part in the gage length sometimes causes necking due to contraint of extensometer ridges. After introducing 24 slits on each ridge in the conventional uniaxial creep specimen, deformation under quasi static loading in tension is examined employing 2.25Cr-1Mo steel. Both experiments and elasitc-plastic FEM analyses show that the new specimen with slits prolongs uniform deformation, and that breaking deformation of the modified specimen is larger than that of the conventional one.

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This paper presents a elasto-plastic FEM program for two-dimensional problems based on the incremental theory. Today, current commercial FEM programs have been used as a versatile tool for simulating engineering problems. The versatile FEM program is very powerful and is widely accepted as a design tool. However, most of the programs have many commands and FEM beginners are sometimes puzzled as to how to use the commands. Moreover, the program requires not only computer resources but is also quite expensive. Therefore, we will propose a new compact elasto-plastic FEM program for FEM beginners. Our FEM program has GUI interface on pre-post processing and is so designed to have various user-friendly interfaces.

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An experimental crack detection system is developed based on the natural frequency changes. In the detecting system, we employed a Maharanobis discriminant analysis, which is a useful way of determining similarity of an unknown sample set to a known one. Monitoring the Mahalanobis distance of unknown specimen and comparing the distance of the specimen with that of un-cracked specimens, we can detect a crack position and a crack depth simultaneously. Using both the statistical classification method and Excel macro program, we have accomplished the real-time detecting system.

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